Dutch architecture studios design a church-turned-pool, where you can walk on water

“Imagine swimming the backstroke with a view of a church vault and stained-glass windows,” says MVRDV founding partner Winy Maas. Well, soon you’ll be able to.

Dutch architecture studios MVRDV and Zecc Architecten have just unveiled their heavenly plans for Holy Water, a public swimming pool inside the former St Francis of Assisi Church in the city of Heerlen.

Holy Water will take over the nave of the 1923 church, which has been empty for two years, and turn it into a social space with a pool at its heart. And here’s the particularly divine twist: the pool has an adjustable floor, which means it can be hidden entirely (making the space flexible for different uses), or the entire room can be flooded with a shallow layer of water so visitors can “walk on water inside the church”, according to a statement by MVRDV.

“By covering the entire pool area with a small layer of water, you can also create a beautiful visual effect, allowing the church to return to its original form and appear even larger and more impressive through the reflection,” Maas adds.

The design keeps much of the church’s character intact while cleverly reimagining the space. Church pews will be repurposed as poolside seating and café furniture, while stained glass windows will still bathe the space in coloured light. As for the old pulpit? That’s the new lifeguard seat.

Visitors will be able to wander the aisles of the old church and peer into the pool through arched windows, which lead to changing rooms and a cosy café tucked at the back. The whole space will be finished with a bespoke mosaic floor designed in collaboration with local artists — a nod to Heerlen’s vibrant mural culture.

Of course, transforming a century-old church into a swimming facility isn’t exactly a walk in the park — or, in this case, a taban in the shallow end.

One of the major design hurdles is keeping the space warm and sustainable without damaging the building’s delicate historical features. The solution involves smart compartmentalisation using glass walls, insulation fitted from the outside, and discreet air systems tucked away in the basement. Even the original church roof will be preserved, complete with sound-absorbing panels to keep the acoustics in check.

But for Maas, the challenge is worth it.

“The vacancy rate of churches is increasing, so we need to come up with new, creative ideas for what we can do with these buildings,” he explains. “Why not give these churches a social function again, as they used to have? A public swimming pool is ideally suited for this.”

Don’t put your swimsuits on quite yet, though: the pool is expected to be open in 2027.